1. Field of the Invention
The present invention relates to a fluidic device.
2. Description of the Related Art
For the purpose of achieving high precision and high efficiency in chemical analyses, fluidic devices referred to as microchemical chips, for example, are used that enable such operations to be performed in a micro size as measurement of potential, measurement of flow rate, and injection, discharge, and assessment of a sample necessary for chromatography and electrophoresis. A microchemical chip is provided with a substrate made of semiconductor or glass in which a channel is formed, a power source such as a micro pump to flow a fluid that is to be treated, to the channel, and a function portion for performing various measurements and analyses and syntheses on the fluid that is to be treated.
In a microchemical chip, a micro electromechanical system (hereinafter, referred to as an “MEMS”) is used for performing a mechanical operation such as transportation of a sample. An MEMS has various components. As one example of the MEMS, there are sensors such as an accelerometer and a pressure sensor for detecting, for example, a change in pressure of a fluid, caused on a main face of a semiconductor substrate according to a chemical change. Other examples of the MEMS have a mechanism, for example, in which a micro pump is combined with a function portion of an optical device that includes a micro mirror device having a movable fine mirror member used for changing an optical axis in order to perform detection at high precision when optically detecting a change caused according to a chemical change. For example, a semiconductor device in which this MEMS is formed is connected to a channel substrate in which a channel is formed such that the MEMS is disposed in an inside portion of the channel, thereby forming a microchemical chip to flow a fluid through the channel and for analyzing the fluid flowing through the channel (see Japanese Unexamined Patent Publications JP-A 2002-214241 and JP-A 2001-108619, for example).
For example, in a conventional fluidic device serving as such a microchemical chip, a fluid is supplied from a separately provided supplying apparatus. The supplying apparatus is provided with a storage portion and ejecting means such as a nozzle, and a fluid stored in the storage portion is ejected from the ejecting means and supplied to the fluidic device. In this manner, in a conventional fluidic device, a storage portion of a fluid is separately provided. Accordingly, the fluid is exposed to the air between the storage portion and the fluidic device, so that foreign materials such as germs and dirt are mixed with the fluid, and thus there is a problem in that so-called contamination is included in a liquid. When the supplying apparatus and the fluidic device are connected to each other via a tube or the like, contamination inclusion can be reduced, but a tube is additionally required, and thus there is another problem in that the components of the entire fluid apparatus including the fluidic device become complicated and large.
Furthermore, in a case where a conventional fluidic device is used, it is difficult to make an apparatus small. Thus, a large apparatus is used, and the entire system through which a fluid becomes large. Accordingly, it is difficult to cause a fluid to flow in a small flow rate through the fluidic device, so that there are problems in that a large amount of the fluid is necessary and in that the efficiency becomes poor.